Ratchet mechanism



Sept. 16' 1924.v

F. E. FARLEY RATCHET MfgcHANIsM Filed June 21 1923- ATTORNEY Patented Sept. i6, i924. y. l i FFLCE.

FRED E. FARLEY, or Gla-Erinnern,MASSACHUSETTS. `Assistme To eooDnnL-rRAm'r COMPANY, or ennnnrrnnn, r/iasseennsnmrs, A eonr'onnrron"onfiyrnssndnl SETTS.

' RATCHET `MIEC:[-Ilfiilhl'ISll.

,Application filed J'iinc 2.1K, 19,23. Serial No'. 646,774. 'To all whom t may concern.' lllgth, with alpair .of resses 3 disposed at Be it known that I, Fnnn E. FARLEY, a opposite sides ofoa line passing transversely citizen of the United States of America, rethrough the `axial center of the shaft in" one siding' at Greenfield, Franklin County, Masdirection, but both on the salme side of a line f 5 sachusetts, have invented .new and useful passing through said axial centeriny a`direc `60 Improvements in Ratchet Mechanism, lof tion perpendicular to` said 'first line. The which the following is a specication. e v side walls of the recesses 3 extend parallel This invention relates to improvements in with the sha-ft, while the bottom walls as il-V ratchet mechanism, the principal object of lustrated herein are of stepvformation, lthat 10 the invention being to provide a mechanism is to say, they comprise two horizontal por: 65

of this character which is simple in conp tions'at different levels and an iliclinedpon structure and strong and durable in operation uniting `said horizontal portions. If ti011- l desired, beweren the inclined. nertonmight A further lobject of the invention is to be continued from the lower` horizontal por; l5 provide a ratchet mechanism in which the tion to the opposite. side wall ofthe recess, 70 parts are held in position insuch a manner without the formationy of a second horizons that when the device is being disassembled tal portion, this llatter portion be'ingformed every part will remain in place until manu- -merely for convenience in machining ally removed, thereby eliminating liability Mounted in therecesses are a.v pair of :0 of loss of any of the parts. i pawl-forming strips e, `which' arent legs 75 WVith the foregoing and ,other objects thickness than the Width of the @CGS-SGS, and view, which willappear asV the description are adapted to be rocked laterally, ofthe i proceeds, the invention consists in the novel shaft on lone of vtheir side edges parallel features of construction and combination of with the axis ofthe shaft, from one side of 5 parts, which will be more fully described their lrespective.recesses toward the other..80 hereinafter and, particularly pointed out in The` pawlsare of such width thatwh'en `in the claim. their operative position adjacent to and In the drawings accompanying and form-v parallel vwith the outer sidewvvallsof ,thereing part of this specification, cesses, ythe upper outer corners of the pawls 3 Fig. l is a partly sectional side View of a project out` beyond the periphery of theS' Y.

ratchet mechanism embodying the features shaft, while uwhen rocked to linoperat-ivel po# of the presentl inventiong' sition `the pawls lie `lwflholly within said pe,- tFig. 2 is a plan view of the cam disk showriphery. For normally Y.retaining the vpawls ringthe form of cam for operating the pawls; in their operative position, a spring 5 is profs Fig. 3 is a transverse section taken on the vided, shownvherein as 4a helical spring seatf90 line 3&3 of Fig. l, showing the shaftropered in a circumferential recess' ,or groove ating handle broken away; formed in the shaft. The ,opposite ends ,of Fig. 4- is a fragmentary end View Von an .the spring are bentv to form hooks for en? enlarged scale, illustrating the cam end of gagement with thelongitudinalupperfedges t-he shaft with one of the pawls in its inopof Ithe pawls, each `of said -pa-wils being pro- 95 erative positions` the cam being shown in vided with arecess lor notch .6in which the dotted lines; hooked endl of the spring rests, vthereby to Fig. 5 is a fragmentary and partly secprevent longitudinal shiftingof the p awl.y tional view of the same end of the shaft il- The shaft is provided with a secondcircumlustrating both pawls in ytheir ratcheteenfeiential grooveadjacentf`to theinnerends 100 gaging position, and showing the means for ofthe pawls, in which grOQNeisseCured retaining them in such position; and spring wire ring 7, which bears against the Fig. 6 is a view similar to Fig. @but il ends of the pawls, and assists in retaining lustrating the opposite pawl in inoperative them against longitudinal movement.

posit-ion. A gear wheel 8 is mounted on the shaft 105 The same characters of reference desigfor free rotation vtheeron, said gear wheel nate the same parts in the different figures being shown herein as provided with two of the drawings. concentric sets of teeth 9 and l0 for trans- Referring to the drawings, 2 designates a mitting motion from the shaft at different spindle which is provided in a portion of its Speeds. rlhe hub l1 of the gear wheel is 1,10

provided interiorly thereof with a series of notches 12 forming ratchet teeth for cooperation with the pawls hereinbefore described, the ends of the teeth being flattened to provide a bearing surface for the shaft. The shaft is provided with a crank handle or lever 13, said handle having formed integral therewith a collar 14 adapted to snugly fit the shaft and be secured thereon by means of a pin or key passing through a transverse opening 15 in the collar and engaging a flat portion 16 formed in the periphery of the shaft in the well known manner. The collar is provided with a pair of notches 17 to receive the upper outer corners of the pawls when in their operative position.

For rocking` the pawls into their inoperative position, a cam disc 18 is provided, said disc being secured on the end of the shaft for rotation relatively thereto by means of a stud 19. The disc is provided at the side thereof adjacent to the end of the shaft with a cam member 20 having an opening of the form shown in Fig. 2. The pawls extend beyond the end of the shafta distance equal to the depth of said opening, as shown in Fig. 1, so that when the disc is secured on the shaft the ends of the pawls project into the cam opening in the disc.

The operation of the device is as follows: lVhen the cam is in its central position, both of the pawls are in their operative position parallel with the side walls of their recesses 'lhis position of the parts is illustrated in li ig. 5, wherein the cam opening is shown in dotted lines. In this position of the pawls there is no ratchet action. That is to say, the shaft and gear are locked for rotation together in both directions. Upon rotation of the cam disc toward the left from t-he position shown in Fig. 5, the cam projection 21 at the right of the shaft comes into con tact with the upper edge of the right-hand pawl and rocks the pawl inwardly against the tension ofthe spring, throwing it into the position shown in Fig. 4t. TWhen the pawl has reached the limit of its inward motion, the cam portion 22 will have come into contact with the outer side of the pawl and will thus retain it in inoperative position. rIhe disc is then at one of its eXtreme positions, and the pawl l at the left-hand side of the shaft will slide over the ratchet teeth when the shaft is rotated toward the left, but will engage said teeth when rotated toward the right, so as to lock the gear to the D therewith.

shaft for rotation therewith. If the disc is then rotated to its opposite extreme position, the cam portions 21 and 252 at the left will act on the left-hand pawl in the saine manner as above described with reference to the right-hand pawl, thus throwing said lefthand pawl into inoperative position as shown in Fig. G, the right-hand pawl having in the meantime returned to its operative position under the action of the spring 5, so that if the shaft is now rotated toward the right the pawl will slide over the ratchet teeth, but upon rotation of the shaft toward the left the pawl will engage said teeth and thus lock the gear to the shaft for rotation A s hereinbefore lstated, when the cam is in its central or neutral position, both p'awls engage the ratchet teeth so that the gear is rotated with the shaft in both directions. rIhe outer face of the disc may be marked with appropriate letters, as in dicated in dotted lines in Fig. 2, to designate the three positions of the disc.

TWhile I have described in detail the de vice herein illustrated, i-t is to be yundc-n'stood that I do not thereby confine my invention to the precise features of construction shown, as I am aware that many mechanical changes and modifications may be made therein without departing from the spirit and scope of the claim appended hereto.

Having` thus described my invention, what I claim is:

A ratchet mechanism, comprising shaft provided with a pair of longitudinally extending recesses, a gear wheel mounted for rotation on said shaft and having a hub provided with internal ratchet teeth, a roclrable pawl in each of said recesses and adapted to project beyond the periphery of said shaft into engagement with said ratchet teeth thereby to loclr the shaft and gear wheel for rotation together, said shaft han ing a circumferential recess, a spring disposed in said recess engaging both of said pawls to retain them in operative position, a rotatable cam-disc, and a pair of cam members for each of said pawls, one of said members being adapted to roch its pareri against the tension of said spring out of engagement with said ratchet teeth, and the other of said members being adapted to lock said pawl in its disengaged position.

In testimony whereof I have signed my name to this specification.

FRED E. FBL'EY. 

